Bosch is original manufacturer of the Vanagon alternators. 90 amp - Bosch brand is considered top of the line and in our experience has much higher success rate than off brand rebuilders who may not be as thorough in their replacement of parts when they rebuild them. IMPORTANT When purchasing this product you will be charged an additional fee listed below as a core charge to insure that you return your old part. Upon receipt of your old part we will promptly credit your credit card for this core deposit fee. Old part must be returned in original manufacturer's box for credit! Sold as each not a pair.